Memories “lost” to Alzheimer’s can be retrieved; they’re not destroyed after all, new science discovers

Alzheimer’s disease is a devastating condition, known for its potential to wipe away its sufferers’ most treasured memories — but recent research has inspired new hope for those who struggle with memory loss. A team of scientists from Columbia University Medical Center has discovered that it may be possible to retrieve memories otherwise thought to be “lost” to Alzheimer’s.

Published in the journal Hippocampus, the team’s research suggests that Alzheimer’s disease does not totally erase memories; instead, they say it just interferes with the brain’s ability to recall information. While their discoveries were found using mice with the condition, if the same holds true for humans, the findings could be revolutionary. The notion that Alzheimer’s simply disrupts memory recall, rather than destroys memories completely, could change the way Alzheimer’s disease is viewed entirely and possibly open many doors for new treatment protocols.

The study’s lead author, Jennifer Perusini, Ph.D., used mice that were developed to enable researchers to record recalled memories in the brain. A yellow fluorescent dye is used to permanently mark neurons when they record a new memory. When the mice recall a memory, red fluorescent dye permanently marks any cells that were activated. When red and yellow dyes overlap, it represents what’s known as a “memory trace.”

Dr. Christine Denny, the study’s senior author, commented, “This has exciting implications for those of us who research the brain. If we find that memories are still stored in the brains of people with Alzheimer’s disease, we may be able to develop treatments, or use existing therapies such as deep brain stimulation, to help people regain access to these memories.”

The team utilized their specially developed mice to examine memory formation and recall in healthy mice and mice with Alzheimer’s disease. Both sets of mice were trained to associate the scent of lemon with a mild shock. A week after learning this association, both groups of mice were tested again. The healthy mice recalled what the lemon scent meant and froze with fear. In contrast, the Alzheimer’s mice only stopped about half as often as the healthy mice.

By looking at the mice’s neurons, the researchers were able to identify a possible cause of this problem. In the Alzheimer’s mice, the yellow dye showed that a memory of the lemon scent had been recorded, but that when the mice smelled it — a different neural pathway was retrieved, suggesting that a different memory was being recalled. But, with a laser light treatment developed by the team, the Alzheimer’s mice were better able to recall the correct memory and respond to the lemon scent accordingly.

Dr. Denny commented, “The next step is to determine if the same memory storage and retrieval mechanisms exist in people with Alzheimer’s disease.” However, the exact same technology will not be able to to be used in humans; viruses were used to engineer the mice neurons and make them light-sensitive — a practice that we will hopefully never see approved for human use.

However, this study still sparks hope that with certain types of therapies, the human brain can be “assisted” in recalling memories. While many foods have been found to help prevent Alzheimer’s disease, natural therapies to help improve the condition once it starts are still needed.

Dementia currently affects 47 million people around the world — but that number is expected to increase dramatically as the population ages. By 2020, as many as 75 million people could be suffering from some form of dementia. While prevention is the true key to battling any disease or condition, this new research certainly provides insight into what’s really happening in the mind of a patient with Alzheimer’s. The memories are there, they just can’t access them.

Perhaps this research will inspire more natural remedies or therapies to assist with improving memory recall and preventing Alzheimer’s disease. Mike Adams, the Health Ranger, and director of CWC Labs, recently authored an article describing how the horsetail herb can help to prevent Alzheimer’s disease and other health issues caused by aluminum, for instance. Hopefully, there will be more natural therapies for Alzheimer’s disease on the horizon, as well.